i have a 91 si with stock ecu and harness with a SOHC zc vtec, i want to hook vtec up to a switch for now, cause im broke.. can i just run a power switch to the solenoid and engage and disengage when i want to for now? and what do i need to do with the pressure sensor undernieth the solenoid?

 

You could but you won't get the added fuel you need.

Save up some money do some research and do it right the first time.

There are roughly 1,529,717 threads on doing this.